On May 14, 2009, at 6:04 PM, Waldemar Horwat wrote:
> Brendan Eich wrote:
>> On May 14, 2009, at 1:47 PM, Waldemar Horwat wrote:
>>> This whole thing is another nail in the coffin of generators.
>>> Generators are the root of the troublesome longjmp's which don't
>>> play well with others.
>> Are you talking about generators, or lambdas?
>> Generators. They cause control flow to jump around between two
> independent functions.
>> THe same problem occurs without lambdas:
>> function gen(arg) {
> try {
> yield 1;
> yield 2;
> } finally {
> alert("Finally called up to three times?!");
> }
> }
>> That finally will be called either 1, 2, or 3 times depending on
> what the caller does, which violates the principle that finally is
> called exactly once, no matter how you leave a scope.
Did you actually test this? Firefox 2 and up work the same.
js> g = gen()
[object Generator]
js> g.next()
1
js> g.next()
2
js> g.next()
typein:6: ReferenceError: alert is not defined
js> alert=print
function print() {
[native code]
}
js> g = gen(42)
[object Generator]
js> g.next()
1
js> g.next()
2
js> g.next()
Finally called up to three times?!
uncaught exception: [object StopIteration]
Exactly one finally.
/be